Semiconductor device fabrication method using an interface control layer to improve a metal interconnection layer

ABSTRACT

A method for fabricating a semiconductor device having an aluminum (Al) interconnection layer with excellent surface morphology forms an interface control layer having a plurality of atomic layers before forming the Al interconnection layer. In the fabrication method, an interlayer dielectric (ILD) film having a contact hole which exposes a conductive region of the semiconductor substrate is formed on a semiconductor substrate, and an interface control layer having a plurality of atomic layers continuously deposited is formed on the inner wall of the contact hole and the upper surface of the interlayer dielectric film, to a thickness on the order of several angstroms to several tens of angstroms. Then, chemical vapor deposition (CVD) completes an Al blanket deposition on the resultant structure, including the interface control layer, to form a contact plug in the contact hole and an interconnection layer on the interlayer dielectric film.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for fabricating asemiconductor device, and more particularly, to a method for fabricatinga semiconductor device having a metal interconnection layer connected toa lower conductive layer via a fine contact.

2. Description of the Related Art

Higher levels of integration in semiconductor devices have lead tocontact holes having smaller diameters and higher aspect ratios.Accordingly, technologies that can effectively fill such fine contactholes have been suggested. A conventional physical vapor deposition(PVD) produces a layer having poor step coverage and thus does notcompletely fill a fine contact hole. As an alternative, chemical vapordeposition (CVD) can fill a contact hole with tungsten (W), forming atungsten plug. However, tungsten plugs have high resistivity andincrease contact resistance. Contact resistance increases further when atungsten plug reacts with an aluminum (Al) interconnection layer formedthereon. Blanket deposition of aluminum provides a relatively lowresistivity material that does not react with aluminum interconnectlayers. However, as the thickness of a CVD deposited Al layer increases,the surface morphology of the Al layer becomes more irregular whichmakes filling of contact holes difficult.

SUMMARY OF THE INVENTION

In accordance with an aspect of the present invention, a fabricationprocess forms an interface control layer before a blanket deposit of aconductive layer of aluminum or a similar material. The interfacecontrol layer is a thin layer typically including multiple atomiclayers. The interface control layer provides uniformly and denselydistributed nucleation sites from which the conductive layer growsuniformly. Accordingly, the fabrication process forms a smooth-surfacedaluminum layer that can fill fine contact holes.

In accordance with one embodiment of the present invention, asemiconductor device includes an interlayer dielectric (ILD) film havinga contact hole on a semiconductor substrate. The contact hole exposes aconductive region of the semiconductor substrate. The fabrication methodforms an interface control layer having multiple atomic layers depositedon an inner wall of the contact hole and an upper surface of theinterlayer dielectric film and then deposits Al on the interface controllayer by a chemical vapor deposition (CVD) to form both a contact plugin the contact hole and an interconnection layer connected to thecontact plug. Between forming the interface control layer but afterforming the ILD film, an ohmic layer can be formed on the exposedconductive region of the semiconductor substrate, the side wall of thecontact hole in the interlayer dielectric film, and the upper surface ofthe interlayer dielectric film; and a barrier layer such as a Ti-richTiN layer can be formed on the ohmic layer.

An atomic layer deposition (ALD), cyclic CVD or digital CVD can form theinterface control layer by depositing a single metal or an alloy film.For example, the interface control layer can be a thin aluminum (Al)film containing silicon (Si). To form such interface control layer, aflow of Si-containing gas is applied a structure including the barrierlayer, to adsorb Si to the surface of the barrier layer, and then excessSi-containing gas is removed from around the structure. Applying anAl-containing gas to the resultant structure adsorbs Al to the surfaceof the barrier layer and to the adsorbed Si. Then, excess Al-containinggas is removed from around the structure, and these steps are repeatedto form on the barrier layer a thin Al film containing Si. During the Aladsorption, hydrogen (H₂) gas may be supplied together with theAl-containing gas to facilitate deposition of Al.

Forming the contact plug and the interconnection layer can be performedin-situ, in the same processing device or chamber in which the interfacecontrol layer is formed.

The fabrication method can further include adsorbing hydrogen ornitrogen to the surface of the interface control layer to form a surfacetreatment layer on the interface control layer, before forming thecontact plug and the interconnection layer. The surface treatment layerprevents oxidation of the interface control layer and maintains thedesired density and uniformity of nucleation sites.

In addition to the above steps, fabrication methods in accordance withother embodiments of the invention can include annealing afterdepositing the Al interconnection layer on the interface control layer.The annealing forms an interconnection layer doped by a diffusion ofatoms from the interface control layer into the interconnection layer.In the method, the interface control layer is typically copper (Cu),titanium (Ti), tungsten (W), silicon (Si), tantalum (Ta) or silver (Ag).

When the interface control layer contains copper, a source gas such as(hexafluoroacetyl)copper(trimethylvinylsilane) [(hfac)Cu(TMVS)], CuCl₂,Cu₂I₄, or a combination thereof is applied to adsorb Cu to the surfaceof the barrier layer. To form multiple atomic layers, the chambercontaining the resultant structure is purged using a purging gas, andthen applying the copper containing gas and purging are repeated.Annealing for diffusion of copper is typically performed at 300 to 650°C.

When the interface control layer is formed of Ti, a gas such as TiCl₄,tridiethylamine titanate (TDEAT), tridimethylamine titanate (TDMAT), ora combination thereof is flushed across the surface to adsorb Ti.

When the interface control layer is formed of W, the flushing isperformed with WF₆ gas.

When the interface control layer is formed of Si, a gas such as SiH₄,SiH₃Cl, SiHCl₃, Si₂H₆, SiCl₄ or a combination thereof is flushed. Here,annealing may be performed at 400 to 650° C.

Another method for fabricating a semiconductor device includes formingan interlayer dielectric (ILD) film having a contact hole that exposes aconductive region of a semiconductor substrate. A first interfacecontrol layer as a thin Al film containing Si is formed on the innerwall of the contact hole and the upper surface of the interlayerdielectric film, to a thickness on the order of several angstroms toseveral tens of angstroms. Then, a second interface control layer havinga plurality of atomic layers of a material such as Cu is formed on thefirst interface control layer, and an Al blanket deposition is performedon the resultant structure by chemical vapor deposition (CVD), to form aconductive layer filling the contact hole and simultaneously coveringthe upper surface of the interlayer dielectric film. Annealing theresultant structure forms an Al interconnection layer doped with Si andCu.

Between forming the first interface control layer and forming the ILDfilm, an ohmic layer can be formed on the exposed conductive region ofthe substrate, the side wall of the interlayer dielectric film in thecontact hole, and the upper surface of the interlayer dielectric film,and then a barrier layer is formed on the ohmic layer. The firstinterface control layer is formed on the barrier layer.

Atomic layer deposition (ALD), cyclic CVD or digital CVD can form thefirst and second interface control layers, and the first interfacecontrol layer, the second interface control layer and the conductivelayer can be formed successively formed in-situ in the same depositionchamber. In one embodiment, between forming the conductive layer andforming the second interface control layer, a surface treatment layer onthe second interface control layer is formed to prevent oxidation of thesurface of the second interface control layer.

According to an aspect of the present invention, a semiconductor devicefabrication method forms an Al interconnection layer having excellentsurface morphology and thereby improves reliability of theinterconnection layer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1A to 1E illustrate structures formed during a semiconductordevice fabrication method according to an embodiment of the presentinvention. FIG. 1A shows an interlayer dielectric (ILD) film 20 on asemiconductor substrate 10. ILD film 20 includes a contact hole Hi thatexposes conductive region 12 of semiconductor substrate. ILD film 20 canbe any type of dielectric of insulating layer that separates conductivelayers in a semiconductor device. In an exemplary embodiment, ILD film20 is an oxide layer, and known oxide deposition and patterning of thedeposited oxide layer form ILD film 20.

Referring to FIG. 1B, conventional chemical or physical vapor depositionprocesses form an ohmic layer 32, e.g., Ti layer, on inner walls ofcontact hole H1 and on a top surface of ILD film 20, and a barrier layer34 on ohmic layer 32. In the exemplary embodiment, barrier layer 34 is aTi-rich TiN layer containing a higher Ti content than a regular TiNlayer. A conventional CVD or PVD process can form the Ti-rich TiNbarrier layer. In the conventional CVD process, the ration of NH₃ toTiCl₄ can be decreased in order to increase the amount of TiCl₄ used andincrease the amount of Ti in the deposited layer. In the PVD process,the reactive gas ratio of N₂ to Ar can be decreased to increase theamount of Ar relative to the amount of N₂.

Referring to FIG. 1C, an atomic layer deposition (ALD), a cyclicchemical vapor deposition, or a digital chemical vapor deposition formsan interface control layer 42. Atomic layer deposition, cyclic chemicalvapor deposition, or digital chemical vapor deposition are processeswell know in the art and can be performed in the conventional manner toform thin layers. In the exemplary embodiment, interface control layer42 is an aluminum (Al) film containing silicon (Si) and includesmultiple atomic layers. Interface control layer 42 is on the inner wallof contact hole H1 and the upper surface of ILD film 20 which have beencovered with ohmic layer 32 and barrier layer 34. Interface controllayer 42 has a thickness of several angstroms to several tens ofangstroms, e.g., 3 to 50 Å, and preferably, less than 10 Å.

An advantage of ALD in forming interface control layer 42 is that ALDcan form highly densified thin layers by supplying required source gasesin sequence. Thus, when CVD forms an Al layer several thousands ofangstroms thick on interface control layer 42, the Al layer can have asmooth flat surface morphology and completely fill contact hole H1,which has a large step difference and a high aspect ratio.

In the exemplary embodiment, ALD that forms interface control layer 42supplies a flow of Si-containing gas, such as silane (SiH₄), at about100 sccm (standard cubic centimeter per minute) for about 30 seconds orless in a carrier gas such as H₂, Ar, or He at about 100 sccm, and thesemiconductor structure including barrier layer 34 is in an ALD chamberat 300 to 800° C., preferably about 320 to 420° C. and a pressure ofabout 0.1 to 5 torr, preferably 0.5 to 1.5 torr. Under these conditions,SiH₄ decomposes so that Si atoms are adsorbed to barrier layer 34.SiH₃Cl, SiH₂Cl₂, SiHCl₃, Si₂H₆ or SiCl₄ also can be used as theSi-containing gas. Excess Ti in Ti-rich TiN barrier layer 34 reacts withSi from SiH₄ to improve adsorption of Si to barrier layer 34.

After the Si adsorption, excess SiH₄ is removed from around thestructure by purging or pumping out the chamber containing thestructure. Then, a flow of an Al-containing gas, such as trimethylaluminum (TMA), is supplied to barrier layer 34 to which Si atoms havebeen adsorbed. As a result, the methyl group of the TMA vaporizesthrough a reaction 1 between TMA and SiH₄ on the surface of barrierlayer so that Al atoms are adsorbed to barrier layer 34.

Reaction 1: Al(CH₃)₃+SiH₄→Si—Al+CH₄(↑)

To promote the Al adsorption, H₂ gas is provided together with the TMA,so that a reaction 2 also occurs.  Reaction 2: Al(CH₃)₃+H₂→Al+CH₄(↑)

In the exemplary embodiment, the flow rate of the Al-containing gas is10 sccm or less, preferably 2 to 3 sccm for between about 0.1 secondsand about 300 seconds, in a carrier gas of (H₂, Ar, or He) with a flowbetween 0 and 500 sccm, preferably about 80 to 120 sccm. The pressure inthe chamber is between about 0.1 and 5 torr, preferably between 0.5 and1.5 torr, and the temperature in the chamber remains between about 320and 420° C. Dimethylamluminum hydride (DMAH), dimethylethylamine alane(DMEM) or triisobutylaluminum (TIBA) also can be used as theAl-containing gas. After the Al adsorption (or deposition) is completed,excess TMA is purged from the chamber containing the semiconductorstructure.

The above-described Si and Al adsorption processes are repeated as manytimes as required to form interface control layer 42 having a desirablethickness, for example between 3 and 10 Å. The deposition rate ofinterface control layer 42 is controlled to produce a highly densifiedAl layer containing Si, which has a uniform grain size. Then, when CVDforms an Al interconnection layer on interface control layer 42, the Alinterconnection layer grows uniformly from uniformly and denselydistributed nucleation sites. The Si atoms in interface control layer 42precipitate along Al grain boundaries and within grains, therebypromoting uniform distribution of Al nucleation sites and preventing Alagglomeration. Otherwise, Al easily agglomerates, and the Al layer growsrapidly at specific nucleation sites as a thickness of the Alinterconnection layer increases. Thus, it is important to control adeposition rate of interface control layer 42 to ensure grain excellentcrystallization characteristics and a high density of close nucleationsites.

ALD forms interface control layer 42 in the above embodiment.Alternatively, cyclic CVD or digital CVD can form the interface controllayer 42. Interface control layer 42 is formed in units of atomic layersin which uniform grains are densely formed. Accordingly, makinginterface control layer 42, which has a number of dense and uniformatomic layers, requires a comparatively low deposition rate, so thatuniform Al nuclei are randomly distributed on barrier layer 34.Typically, the deposition rate of a Al interconnection layer is higherthan that of interface control layer 42, but the Al interconnectionlayer still forms with a uniform surface morphology.

Referring to FIG. 1D, a hydrogen-containing gas such as hydrogen (H₂) orsilane (SiH₄) or nitrogen-containing gas such as ammonia NH₃ is suppliedto the surface of interface control layer 42, so that hydrogen ornitrogen is adsorbed to interface control layer 42 and forms a thinsurface treatment layer 44 on interface control layer 42. In theexemplary embodiment, the reaction chamber containing the semiconductorstructure including interface control layer 42 is filled with hydrogenor ammonia at a pressure between about 0.1 and 50 torr, preferably about1 torr, at a temperature between about 200 and 500° C., preferablybetween about 380 and 420° C. The gas flow rate is between about 50 and500 sccm, preferably about 100 sccm, for a period between about 30seconds and 30 minutes, preferably about 1 minute. Surface treatmentlayer 44 helps prevent oxidation of interface control layer 42 if thesemiconductor structure is exposed to air before formation of theinterconnection layer, for example, when moving the semiconductorstructure to another processing apparatus for formation of aninterconnection layer. However, forming treatment layer 44 can beomitted when the interconnection layer can be in-situ after forminginterface control layer 42.

Referring to FIG. 1E, a CVD blanket deposition of Al forms a contactplug 52 in contact hole H1 and a 1,000 to 8,000 Å thick interconnectionlayer 50 connected is to contact plug 52 on surface treatment layer 44.In the exemplary embodiment, CVD forming plug 52 and layer 50 uses aflow between 1 and 50 sccm, preferably between 3 and 5 sccm, of TMA in acarrier gas flow between about 10 and 500 sccm, preferably between 90and 110 sccm, through a chamber at a temperature between about 100 and500° C., preferably between 110 and 130° C. and a pressure between about0.1 and 100 torr, preferably between about 0.5 and 1.5 torr. Here,because interface control layer 42 is previously formed in contact holeH1, contact plug 52 can completely fill contact hole H1 andsimultaneously interconnection layer 50 having the excellent surfacemorphology can be obtained.

FIGS. 2A to 2D illustrate a method for fabricating a semiconductordevice according to another embodiment of the present invention.

Referring to FIG. 2A, in the same way as described with reference toFIGS. 1A and 1B, an ILD film 120 having a contact hole H2 is formed on asemiconductor substrate 110; an ohmic layer 132 is formed on inner wallsof contact hole H2 and an upper surface of ILD film 120; and a TiNbarrier layer 134 is formed on ohmic layer 132.

Then, ALD forms an interface control layer 142, which is made of copper(Cu), titanium (Ti), tungsten (W), silicon (Si), tantalum (Ta) or silver(Ag), on the inner wall of contact hole H2 and the surface of ILD film120 which have been covered with ohmic layer 132 and barrier layer 134.Interface control layer 142 contains multiple atomic layers and has athickness of several angstroms to several tens of angstroms, preferably,less than 20 Å.

In an exemplary embodiment described further below, interface controllayer 142 is Cu. In an ALD for forming Cu interface control layer,(hexafluoroacetyl) copper (trimethylvinylsilane) [(hfac)Cu(TMVS)],CuCl₂, Cu₂l₄ or a combination thereof, as a source gas of Cu, is flushedon barrier layer 134, so that Cu atoms are adsorbed to barrier layer134. The exemplary ALD process use a flow of (hfac)Cu(TMVS) at a flowrate between 1 sccm and 500 sccm, preferably 10 sccm, at a temperaturebetween about 100 and 400° C., preferably about 220 to 270° C., and apressure between about 0.1 and 100 torr, preferably between about 0.5and 1.5 torr, for between 1 second and 10 minutes, preferably about 1minute. Then, excess source gas is purged from around the semiconductorstructure using hydrogen (H₂), helium (He) or argon (Ar) gas. Theflushing and purging are repeated as many times as required to forminterface control layer 142 formed of multiple thin Cu atomic layersdeposited in sequence.

When interface control layer 142 is Ti, TiCl₄, tridiethylamine titanate(TDEAT), tridimethylamine titanate (TDMAT) gas or a combination thereofis used as a source gas. When interface control layer 142 is W, WF₆ gasis used; and for a Si interface control layer, SiH₃Cl, SiH₂Cl₂, SiHCl₃,Si₂H₆, SiCl₄ gas or a combination thereof is used. Process parametersfor the ALD process vary according to the source gas.

Referring to FIG. 2B, a flow of a hydrogen-containing ornitrogen-containing gas is supplied to the surface of interface controllayer 142, so that hydrogen or nitrogen is adsorbed to interface controllayer 142 and forms a thin surface treatment layer 144 on interfacecontrol layer 142. Surface treatment layer 144 helps prevent oxidationof interface control layer 142.

Referring to FIG. 2C, a CVD blanket deposition of Al fills contact holeH2 and forms conductive layer 150 on surface treatment layer 144. Whenthe CVD blanket deposition is performed in-situ after forming interfacecontrol layer 142, forming surface treatment layer 144 may be omitted.

Referring to FIG. 2C, Al blanket deposition on the semiconductorstructure fills the contact hole H2 and simultaneously forms aconductive layer 150 covering the upper surface of ILD film 120. In theexemplary embodiment, Cu interface control layer 142 promotes uniform Algrain nucleation and prevents Al agglomeration in the CVD blanketdeposition. Accordingly, interconnection layer 150 has excellent surfacemorphology even if interconnection layer 150 is thick. Preferably,forming conductive layer 150 is in-situ after forming interface controllayer 142.

Referring to FIG. 2D, annealing form an Al interconnection layer 150 adoped with Cu by promoting a diffusion of Cu atoms from interfacecontrol layer 142 into conductive layer 150. The annealing is performedat 300 to 650° C., preferably 450 to 500° C., for between 5 minutes and60 minutes, preferably about 30 minutes. For example, when 0.5 atomic%Cu doping in Al interconnection layer 150 a is required, Cu interfacecontrol layer 142 is to be about 20 Å thick. The doping of Alinterconnection layer 150 a improves reliability of Al interconnectionlayer 150 a.

As described above, when CVD forms conductive layer 150 while Cu ofinterface control layer 142 is adsorbed to the TiN surface of barrierlayer 134, an Al conductive layer having excellent surface morphologycan be obtained even if the Al conductive layer is thick. Also, Cu inthe Al interconnection layer 150 a acts as a dopant, thereby improvingreliability of the interconnection layer. An interface control layerformed of Ti, W, Si, Ta or Ag can produce the same effect as a Cuinterface control layer. However, required annealing temperature varydepending on the composition of interface control layer. For example, aTi interface control layer's annealing temperature is about 400 to 650°C.

FIGS. 3A through 3E illustrate a fabrication method to still anotherembodiment of the present invention. Referring to FIG. 3A, an ILD film220 is formed on a semiconductor substrate 210 with a contact hole H3through ILD 220 exposing a conductive region of semiconductor substrate210. An ohmic layer 232 is formed of Ti on the exposed conductive regionof semiconductor substrate 210, the side walls of contact hole H3 in ILDfilm 220, and the upper surface of ILD film 220, and then a barrierlayer 234 is formed of TiN on ohmic layer 232. These layers can beformed in sequence by the same processes described above in reference tocorresponding layers illustrated in FIGS. 1A and 1B.

Then, a first interface control layer 242, as a thin Al film containingSi, is formed on barrier layer 234, to a thickness on the order ofseveral angstroms to several tens of angstroms, preferably, less than 10Å. Again, the same method described with reference to FIG. 1C forforming interface control layer 42 can form first interface controllayer 242.

Referring to FIG. 3B, a second interface control layer 244, which isformed of Cu, is formed on first interface control layer 242 by the samemethod as described with reference to FIG. 2A. Alternatively, secondinterface control layer 244 may also be formed of Ti, W, Si, Ta or Ag,instead of Cu. In this embodiment, second interface control layer 244 iscontinuous thin layers as described above. However, second interfacecontrol layer 244 may include multiple separated islands on firstinterface control layer 242. Such islands can be formed by using a maskto limit formation of second interface control layer 244 to specificareas. Alternatively, selective etching can pattern a continuous layer.

Referring to FIG. 3C, a hydrogen-containing gas or nitrogen-containinggas is supplied to the surface of interface control layer 244 to form athin surface treatment layer 246 on interface control layer 244 in thesame way that was described with reference to FIGS. 1D and 2B. Surfacetreatment layer 246 helps prevent oxidation of interface control layer244, for example, when moving the semiconductor structure to anotherprocessing apparatus.

Referring to FIG. 3D, a CVD blanket deposition of Al fills contact holeH3 and forms conductive layer 250 on surface treatment layer 246. Whenthe CVD blanket deposition is performed in-situ after forming interfacecontrol layer 244, forming surface treatment layer 246 may be omitted.Like the previously described methods, interface control layers 242 and244 promote uniform Al grain nucleation and prevents Al agglomeration inthe CVD blanket deposition, so that conductive layer 250 can have auniform surface morphology.

Referring to FIG. 3E, an annealing of conductive layer 250 forms an Alinterconnection layer 250 a doped with Cu by promoting a diffusion of Cuatoms from second interface control layer 244 into conductive layer 250.The annealing is performed at about 300 to 500° C., preferably, about450 to 480° C. The doping of Al interconnection layer 250 a improvesreliability of Al interconnection layer 250 a.

As described above, an interface control layer formed according to thepresent invention promotes a uniform deposition of an interconnectionlayer which is formed on the interface control layer, so that theinterconnection layer can have a uniform surface morphology. Inaddition, the interface control layer can act as a dopant of theinterconnection layer, thereby improving reliability of theinterconnection layer.

Although the invention has been described with reference to particularembodiments, the description is only an example of the inventor'sapplication and should not be taken as a limitation. Various adaptationsand combinations of features of the embodiments disclosed are within thescope of the invention as defined by the following claims.

What is claimed is:
 1. A semiconductor device fabrication method comprising: (a) forming an interlayer dielectric (ILD) film having a contact hole, the contact hole exposing a conductive region of an underlying structure; (b) forming an interface control layer of a plurality of atomic layers continuously deposited on inner walls of the contact hole and an upper surface of the interlayer dielectric film; and (c) forming a contact plug in the contact hole and an interconnection layer on the inferface control layer by depositing aluminum in the contact hole and on the interface control layer.
 2. The method of claim 1, wherein after step (a) and before step (b), the method further comprises: forming an ohmic layer on the inner walls of the contact hole and on the upper surface of the interlayer dielectric film; and forming a barrier layer on the ohmic layer, wherein the interface control layer is formed on the barrier layer.
 3. The method of claim 2, wherein the interface control layer is an aluminum (Al) layer containing silicon (Si).
 4. The method of claim 3, wherein atomic layer deposition (ALD) forms the interface control layer.
 5. The method of claim 4, wherein step (b) comprises: (b1) flowing a Si-containing gas on the barrier layer, so that Si atoms are adsorbed to the barrier layer; (b2) removing excess Si-containing gas from around the barrier layer; (b3) flowing an Al-containing gas on the barrier layer to which the Si atoms were adsorbed, so that Al atoms are adsorbed to the barrier layer; (b4) removing excess Al-containing gas from around the barrier layer; and (b5) repeating steps (b1) through (b4) to form the Al layer containing Si on the barrier layer.
 6. The method of claim 5, wherein the barrier layer is a titanium (Ti)-rich titanium nitride (TiN) layer.
 7. The method of claim 5, wherein hydrogen (H₂) gas is supplied together with the Al-containing gas in step (b3) to facilitate deposition of Al atoms.
 8. The method of claim 1, further comprising annealing the semiconductor device after step (c), so that the interconnection layer is doped with metal atoms from the interface control layer.
 9. The method of claim 8, wherein after step (a) and before step (b), the method further comprises: forming an ohmic layer on the inner walls of the contact hole and on the upper surface of the interlayer dielectric film; and forming a barrier layer on the ohmic layer, wherein the interface control layer is formed on the barrier layer in step (b).
 10. The method of claim 9, wherein the interface control layer is formed of a material selected from a group consisting of copper (Cu), titanium (Ti), tungsten (W), silicon (Si), tantalum (Ta), and silver (Ag).
 11. The method of claim 10, wherein a method selected from a group consisting of atomic layer deposition (ALD), cyclic CVD, and digital CVD forms the interface control layer.
 12. The method of claim 11, wherein the interface control layer is formed of Ti, and step (b) comprises flowing a gas selected from a group consisting of TiCl₄, tridiethylamine titanate, tridimethylamine titanate, and combinations thereof.
 13. The method of claim 11, wherein the interface control layer is formed of W, and step (b) comprises flowing WF₆ gas.
 14. The method of claim 11, wherein the interface control layer is formed of Si, and step (b) comprises flowing a gas selected from a group consisting of SiH₃Cl, SiH₂Cl₂, SiHCl₃, Si₂H₆ or SiCl₄ and combinations thereof.
 15. The method of claim 10, wherein the interface control layer is formed of Cu, and step (b) comprises: (b1) flowing a source gas selected from a group consisting of (hexafluoroacetyl)copper(trimethylvinylsilane), CuCl₂, Cu₂l₄, and combinations thereof so that Cu atoms are adsorbed to the barrier layer; (b2) purging the source gas from around the semiconductor device after step (b1); and (b3) repeating steps (b1) and (b2).
 16. The method claim 1, further comprising annealing the semiconductor device after step (c) so that the interconnection layer is doped with metal atoms from the interface control layer, and step (b) comprises: (b′) forming a first interface control layer as an Al film containing Si and a plurality of atomic layers on the inner wall of the contact hole and the upper surface of the interlayer dielectric film; and (b″) forming a second interface control layer having a plurality of atomic layers continuously deposited on the first interface control layer.
 17. The method of claim 16, wherein after step (a) and before step (b), the method further comprises: forming an ohmic layer on the inner walls of the contact hole and on the upper surface of the interlayer dielectric film; and forming a barrier layer on the ohmic layer, wherein the first interface control layer is formed on the barrier layer.
 18. The method of claim 17, wherein atomic layer deposition (ALD) forms the first and second interface control layers.
 19. The method of claim 18, wherein step (b′) comprises: (b′1) applying a Si-containing gas to the barrier layer so that Si atoms are adsorbed to the barrier layer; (b′2) removing excess Si-containing gas from around the semiconductor device; (b′3) applying an Al-containing gas to the barrier layer to which the Si atoms are adsorbed, so that Al atoms are adsorbed to the barrier layer; (b′4) removing excess Al-containing gas from around the semiconductor device; and (b′5) repeating steps (b′1) through (b′4) to form the Al film containing Si on the barrier layer.
 20. The method of claim 19, wherein hydrogen (H₂) gas is applied together with the Al-containing gas in step (b′3).
 21. The method of claim 18, wherein the second interface control layer is formed of a material selected from a group consisting of copper (Cu), titanium (Ti), tungsten (W), silicon (Si), tantalum (Ta) and silver (Ag).
 22. The method of claim 21, wherein the second interface control layer is formed of Cu, and step (b″) comprises: (b″1) applying a gas selected from a group consisting of (hexafluoroacetyl)copper(trimethylvinylsilane) ) [(hfac)Cu(TMVS)], CuCl₂, Cu₂l₄, and combinations thereof so that Cu atoms are adsorbed to the barrier layer; (b″2) purging from around the semiconductor device after step (b″1); and (b″3) repeating steps (b″1) and (b″2).
 23. The method of claim 1, wherein step (c) is performed in-situ after step (b).
 24. The method of claim 1, wherein after step (b) and before step (c), the method further comprises forming a surface treatment layer on the interface control layer, the surface treatment layer preventing oxidation of the surface of the interface control layer, wherein Al deposition in step (c) is performed on the surface treatment layer.
 25. The method of claim 24, wherein the surface treatment layer is formed by adsorbing hydrogen or nitrogen to the interface control layer. 